Perhaps it's a generational thing, or maybe it's inevitable -- social media is changing the traditional help desk model in higher education.
You might not want to accept it, or perhaps you choose to cling to what has worked for years. That doesn't matter, because your customers are evolving how they cry out for help. If those cries go unheeded, everything -- from the credibility of the help desk operation to the metrics on tickets closed over a specific period -- becomes invalid.
So what's the change we're talking about? It's Twitter. In 140 characters or less, students are demanding assistance, crying for help, asking general technology questions and saying very unkind things about the IT organization that likely (hopefully) have no basis in truth. It's going on 24 hours a day, in increasing volume. It's what they do, and whether the "official" help desk plays along matters little.